File - In this April 20, 2016 file photo, customers buy products at the Harvest Medical Marijuana Dispensary in San Francisco. California's lopsided U.S. Senate is nearing a historic end and voters are pondering a long list of ballot questions that could legalize marijuana, end the death penalty and slap cigarette smokers with a $2-a-pack tax increase. (AP Photo/Haven Daley, File)

BOSTON (WWLP) – Western Massachusetts sheriff’s want the state to use marijuana tax revenues to help combat the state’s deadly opioid addiction crisis. They’re urging state lawmakers to increase the tax on pot from 10% to 15% to pay for substance abuse treatment programs.

The Massachusetts Committee on Marijuana Policy held their last public hearing on Monday. State Representatives Brian Ashe and John Velis filed a bill that would establish a fund to support addiction treatment programs; services sheriffs said are in short supply.

Hampden County Sheriff Nicholas Cocchi told 22News, “The resources are not there when people are putting their hand up for support, and as my colleague said earlier, corrections is one of the front lines, first lines, of detoxification for people that are coming in.”

Critics argue that increasing the sales tax would encourage criminal activity, and keep people from buying pot legally. “Any increase in the amount of the tax is a gift to the black market and makes it harder for legal stores to stay afloat and compete on price,” said Andy Gaus, the Press Secretary of the Massachusetts Cannabis Reform Coalition.

However, State Representative John Velis, (D) Westfield, told 22News that other states with higher pot taxes still have viable legal markets; “The state’s that have legalized it, Colorado, Washington, and Alaska, that just hasn’t been the case. They’re doing well. It’s a great source of revenue for them. So I think we can do it. We need to do it. People are dying every day.”

Washington has the highest tax on pot sales at 37%, followed by Colorado at 29%. The bill under consideration would impose a 17% tax on pot, including an optional 2% local sales tax.

The committee is expected to recommend changes to the ballot law in June.